The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Gas-liquid separation has become increasingly important in many subsea hydrocarbon production environments to enable and/or improve operations and project economy. In some cases separators operate in a vertical orientation (e.g., Caisson separators or vertical multiple pipe separators), while in other cases separators operate in horizontal orientation (e.g., drum type separators as described in WO 2010/151392, horizontal pipe separators as described in WO 2013/130856). Still further examples for known separators are described in U.S. Pat. No. 4,948,393, U.S. Pat. No. 6,554,066, WO 01/87453, WO 2011/028093, and EP711903B1. All publications identified herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
Unfortunately, where the produced fluids carry sand or other particulate solids (also referred to as “sand” herein), sand accumulation is a major concern in horizontal separators. Sand accumulation in horizontal separators is typically prevented by sand removal upstream of the separator (e.g., de-sanding hydrocyclone, vessel based sand remover, etc.), and/or periodical jetting inside the separator to remove sand. However, and especially where the gas-liquid separators are installed in a subsea environment, upstream sand removal and/or jetting introduce further complexities and potential points of failure, which is particularly problematic in deepwater applications where smaller separators and fewer components in the overall system are desirable. Moreover, and especially where horizontal separators are used, less than desirable degrees of gas-liquid separation can be encountered.
Therefore, even though various separator configurations and methods are known in the art, all or almost all of them suffer from one or more disadvantages. Thus, there is still a need to provide improved gas-liquid separators, especially where the separator is operated in a subsea environment.